1. Field
The present invention relates generally to low-noise amplifier matching devices.
2. Background
Multi-mode, multi-standard wireless communication devices usually require one or more high performance radio receivers, which should provide adequate signal-to-noise (SNR) performance for weak signals to achieve maximum sensitivity performance. Additionally, a multi-mode receiver should linearly handle signal and interference levels over a wide dynamic range with minimal distortion. That is, high linearity performance is needed. Distortion within a receiver may be caused by, for example, intermodulation and gain compression. Higher linearity results in reduced intermodulation levels and gain compression. Consequently, low noise, high gain performance is also needed. Typically, receiver design techniques, which simultaneously provide both high linearity and low noise, are difficult to achieve and are subject to design compromises.
One important constituent of a high performance receiver is a low-noise amplifier (LNA). An LNA may be a major determinant of the overall noise performance of the receiver. In other words, the characteristics of the LNA, such as high linearity and low noise, may dominate the overall receiver performance. Generally, an LNA is placed at the front-end of a receiver, near a receive antenna interface, to minimize radio frequency (RF) losses between an antenna and the LNA. The LNA is designed to provide high gain while contributing a minimal amount of excess noise beyond the noise appearing at an LNA input. This property is known as a low noise figure. To achieve a high linearity characteristic, the LNA should also have a high third-order input intercept point (IIP3), which is an input level where the third-order intermodulation product level equals the extrapolated linear desired output level. In general, a high value of IIP3 indicates high linearity performance.
Transceiver devices are shrinking in size while adding more LNAs to cover more frequency bands and more modes. Conventional RF transceiver application specific integrated circuits (ASICs) may include at least 20 LNAs to cover low bands (600 MHz to 960 MHz), middle bands (1400 to 2100 MHz) and high bands (2200 MHz to 2700 MHz). Device packages including at least 20 LNAs may be around 3.8 millimeters by 3.8 millimeters, yet the passive matching components for each LNA occupy area three times the size of a transceiver device. Moreover, each LNA must be manually impedance matched for best noise figure and gain, thus, consuming additional time. Accordingly, receiver LNA matching takes up a large amount of area, and requires significant effort to change each part. A typical LNA may have two passive matching components and, assuming 20 primary receiver LNAs and 20 diversity receiver LNAs, a receiver can include around 80 passive matching components.
A need exists for an enhanced wireless communication device. More specifically, a need exists for embodiments related to a wireless communication device including a programmable LNA matching device.